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    <title>Document</title>
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<body>
    <script>
        var e = 10;
        console.log(e++ + ++e)
        console.log(10 + e++)//e=13,运算的时候返回的值为12

        //小练习
        var a = 10;
        ++a;
        var b = ++a + 2;

        var c = 10;
        c++;
        var d = c++ + 2;

        var e = 10;
        var f = e++ + ++e
    </script>
</body>

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